Throttle control for internal combustion engines



Aug. 4, 1959 LANDRUM 2,897,807

THROTTLE CONTROL FOR INTERNAL COMBUSTION ENGINES Filed Dec. 8, 1958 s Sheets-Sheet 1 INVENTOR. Porfrae' La nd rum BY mi'orneys 7* T4 w T UW .v V. W W- Filed Dec. 8, 1958 Aug. 4, 1959 P. LANDRUM 2,397,807

THROTTLE CONTROL FOR INTERNAL COMBUSTION ENGINES 3 Sheets-Sheet 2 AH'arneys Aug. 4, 1959 P. LANDRUM 2,397,307

THROTTLE CONTROL FOR INTERNAL COMBUSTION mamas Filed Dec. s, 1958 s Sheets-Sheet a I FIFE 1 11 If? .////A 1A INVENTOR. H Poner La nd ru m ZZL JWW flfforneys THROTTLE CONTROL FOR INTERNAL COMBUSTION ENGINES Forter Landrum, Birmingham, Ala. Application December- 8, 1958, Serial No. 778,760

6 Claims. (Cl. 123-103) This invention relates to control means for the throttle valves of internal combustion engines, and is adapted to be interposed between the usual manual throttle control and the throttle valve of the carburetor of internal combustion' engines.

The principal object of my invention is to provide a throttle control which is effective to open the throttle valve of the engine in accordance with the pressure existing in the intake manifold of the engine, the amount of opening being determined by the setting of the manual control, such for instance, as the usual accelerator pedal.

Another object is to provide apparatus of the character designated which will permit the compression ratios of internal combustion engines to be increased over those currently in use, and to permit such engine to operate under varying conditions of speed and load, with fuels of present average octane ratings, all without damage to the engine and without sacrificing any of the performance of such engine.

More specifically, an object of my invention is to permit the use of high compression ratios by limiting the throttle opening at low engine speed and as engine speed increases to exert anincreasing opening force on the throttle, whereby at low engine speeds the engine is not overcharged and at higherengine speeds the engine is adequately charged.

A more specific object of my invention is to provide apparatus of the character designated in which the actual opening of the throttle valve is determined by the amount of sub-atmospheric pressure existing in the intake manifold of the engine, whereby the throttle valve may be set for the optimum operating position under all conditions of engine speed.

Briefly, my invention comprises a housing through which pass two independently movable, axially aligned shafts. One of these is connected to the throttle valve or the carburetor while the other is connected so as to be rotated by a manual throttle control such as the usual foot pedal. On the shafts are seating vanes which contact the sides and ends of the housing in substantially air-tight manner, whereby to form a fluid tight chamber in the housing. This chamber is connected to the intake manifold and therefore is under sub-atmospheric pressure. A stop means on the manually operated shaft limits the amount of opening movement of the other shaft. Furthermore, the housing is so arranged that as the throttle valve shaft moves toward open throttle position the effective cross sectional area of the vane controlling the throt- States Patent Q l 2,897,807 Patented Aug. 4, 1959 in turn is limited by the setting of the manual throttle control. Preferably, the opposite side of the vane which in the accompanying drawings forming a part of this application in which:

Fig. 1 is an elevational view of my improved apparatus in place on the carburetor of an internal combustion engine, the carburetor in turn being mounted on the usual intake manifold; v

Fig. 2 is a plan view with certain parts broken away and in section; N

Fig. 3 is a detailed sectional view taken generally along line 3-3 of Fig. 2;

Fig. 4 is a detail sectional view taken generally along line 4-4 of Fig. 3; I

Fig. 5 is a detail fragmental elevational view of the shafts and part of the vanes completely removed from the housing of the device;

Fig. 6 is a detail sectional view of the vanes and shaft assembly .taken generally along line 6-6 of Fig. 7;

Fig. 7 is an end elevational View of the shaft and vane assembly with certain parts of the vanes being broken away and in section;

Fig. 8 is an isometric view of one set of the vanes and the springs for holding. them in contact with the housing, the view being with the parts in exploded position and with certain of them broken away and in section;

Fig. 9 is an end elevational view of the end of the butterfly valve opposite the throttle valve control apparatus and showing a spring for urging the throttle valve toward closed position; and,

Fig. 10 is a view corresponding to Fig. 9 and showing an arm and weight arrangement which may be used instead of the spring of Fig. 9 for urging the throttle valve toward closed position.

Referring to the drawings for a better understanding of my invention and particularly to Figs. 1 and 2, my improved apparatus comprises a housing indicated generally by the numeral 10 which is adapted to be bolted or otherwise secured onto the side of a carburetor indicated generally by the numeral 11. As will be under.- stood, the carburetor has one or more throttle control valves 12 therein. The carburetor is secured by bolts or the like 13 to an intake manifold 14 of an internal combustion engine, not shown. Certain internal parts of my improved apparatus are connected infa manner later to be described to a shaft 16 on which the valves 12 are mounted in the customary manner.

The housing 10 of my improved apparatus may comprise ends or heads 17 and 18. Mounted between the heads 17 and 18 are two metal spacer blocks 19 and 21 which are shown more clearly in Fig. 3. A number of bolts 22 pass through the ends or heads 17 and 18 and the and 21. The plates 23 and 24 are held assembled around the ends 17' and 18 and onto the blocks 19 and 21 by means of straps of flexible sheet metal indicated at 26. One end of each strap 26 is anchored to the blocks and 21 by screws 27 .as shown. The opposite ends carry a pair of bolts 28jwhi'ch pass through suitable openings.

in lugs 29 secured to the blocks 19 and 21. Nuts 31 serve to draw the straps tight, thus holding the parts assembled and providing a substantially air-tight hous- Mounted in suitable bearing projections outstanding from the heads 17 and 18 are a pair of generally axially aligned shafts 32 and 33. The shafts are held in alignment by means of a centrally disposed centering pin 34 and the shafts are independently rotatable relative to each other. The shaft 32 is provided in its end adjacent the carburetor with a drilled and tapped hole 36 adapted to receive the threaded reduced end 37 of the throttle valve shaft 16. Thus, shaft 32 is connected to the shaft 16 so that upon rotation of shaft 32 the throttle valves 12 may be moved to open position.

Shaft 33 is provided with a threaded end 35. An arm 38 is secured on the threaded end by means of a nut 39. Pivotally connected in the upper end 'of arm 38 as at 41 is a manually operated throttle controlmember 42 which conveniently may be connected for manual operation to the usual foot pedal found in automobiles. The linkage arrangement is such that when the member 42 and arm 38 move to the right as viewed in Fig. l, the throttle valves are released for opening in a manner later to be explained.

The inside of the housing 10 is divided by the vane means now to be described generally into two compartments 43 and 44. Compartment 43 is connected through a passage 46 to the sub atmospheric pressure existing in the intake manifold 14, whereby the compartment or section 43 of the housing is subjected always to the varying sub-atmospheric pressure existing in the manifold under the different operating conditions of the engine. The compartment 44 is connected through a passage 47 in the housing block 21 to a conduit 48 in turn connected by a rubber hose or the like 49 to the air intake of the carburetor 11, above the valves 12. Thus, filtered air is supplied to the connection 48. Similarly, a passage 51 having a metering valve 52 therein leads to the housing for a purpose later to appear. The block 21 has a slot 53 therein in which is slidably placed a strip sealing element 54 which contacts at its inner end against the sides of the shafts 32 and 33. A spring 56 holds the seating element in fluid tight engagement with the shafts.

The shafts 32 and 33 are provided with enlarged diameter portions 32 and 33, respectively, as shown in Figs. 4, and 6. Welded to the enlargement 32* are are plates 57 and 58 which are just slightly shorter than the distance between the ends or heads 17 and 18. In like manner and diametrically opposite the plates 57 and 58 are other plate 59 and 61, welded to the enlarged diameter part 33 of shaft 33. Spaces are thus defined between the respective pairs of plates.

Fitting in the space between the plates 57 and 58 are blocks of plastic material 62 and 63. As best shown in Flg. 7, these blocks of material are generally L-shaped in cross transverse section, having lower ends 64 which are thlcker than the remainder of the block thereby to provide a shoulder at the lower portions thereof which extends the width and length of each of the blocks 62 and 63. Further, the blocks are notched out as indicated at 66 to provide sliding tongue and groove mating portions. Still further, the blocks 62 and 63 are urged apart by a spring 67, this serving to cause the blocks to contact the end walls or heads 17 and 18 of the housing, thus to seal the compartment 43 at the ends.

Also disposed in the spaces between the plates 57 and 58 and occupying the space defined by the thicker lower ends of. the blocks 62 and 63, are a pair of wiping seal- 1ng members 68 and 69. These members likewise are provided with overlapping tongues 71 which fit slidably together. A spring 72 urges the members 68 and 69 away from each other wherebytheyalso seal against the ends or heads 17 and 18. Further, the members 68 and 69 are urged upwardly by means of springs 73 which fit in holes 74 drilled in the members .68 and 69. The

4 lower ends of the springs fit in blind holes 76 which are drilled in the thicker portion 64 of the members 62 and 63.

It will be understood, from what has just been said, that in the space between the plates 59 and 61 are disposed identical sets of the sealing members just described.- Therefore, a description of these is believed to be unnecessary and the same numerals have been applied to the respective parts located between the plates 59 and 61. It will thus be apparent that in effect the shafts 32 and 33 carry substantially identical sets of sealing vanes. Therefore, the compartment 43 which is bounded on one side by the plates 57 and 58 and sealed by the plastic vane members described is in fact substantially fluid-tight from the atmosphere to which the compartment 44 is connected. Further, the plates 23 and 24 are curved or radii struck from the respective points P and P Fig. 3. The effect of this is that as the vane assemblies carried by the shafts rotate, the effective cross sectional area of the vane assemblies increases. Thus, as the throttle valves move toward open position the unit sub-atmospheric pressure in chamber 43 required to hold the valves open decreases; The importance of this will appear later.

Welded to the enlarged portion 33 of shaft 33 is a stop member 77. This stop member is adapted, when the parts are in the positions of Figs. 1, 2 and 3, positively to contact the plate 57, thus to hold the shaft 32 in its counter-clockwise motion position as viewed in Figs. 1 and 3, namely, in closed throttle position. Further, when the manual control rod 42 is actuated the stop 77 moves to the right, or clockwise, as viewed in Figs. 1 and 3, thereby freeing the shaft 32 and hence the throttle valves to opening movement in response to the vacuum applied through opening 46 into the compartment 43. Therefore, if there exists sufiicient vacuum in the compartment 43 the throttle valves are opened to the degree permitted by the stop 77.-

It will be understood that the shaft 16 and hence the throttle valves 12 are urged toward closed position by suitable means such as the coil spring 78 shown in Fig. 9. If desired, and as modification, spring 78 may be replaced by an arm 79 on the end of which is a weight 81. See Fig. 10.

When first starting an internal combustion engine it is desirable that the throttle control 42 be mechanically connected to the throttle valves in the normal manner. As soon as the engine starts I have provided means effective automatically to disengage the same, thereby to free the valves 12 for actuation in accordance with the manifold vacuum as determined by my'improved apparatus.

In order to effectuate the foregoing I drill a small opening 82 in the enlarged portion 32 of shaft 32. This in effect forms a cylinder. In this cylinder I place a small piston 83 which has a reduced diameter end 84 adapted to fit, when both shafts 32 and 33 are in closed throttle position, into a hole 86 provided in the enlarged diameter part 33 of shaft 33. A spring 87 urges the piston toward the left as viewed in Fig. 6. The opening 82 is connected by a passage 88 to chamber 43. The opposite end of the piston is connected to atmospheric pressure through a passage 89 which opens into the space to the left of the plate 58 as shown in Fig. 3. Therefore, when the engine is at rest and no vacuum is applied to passage 88, spring 87 urges the small end 84 of the piston into the opening 86, thus locking shafts '32 and 33 together. This permits the throttle valvesvto be opened upon actuation of the manual control 42 in the usual manner. As soon as vacuum is applied to the passage 88 the piston is pulled out of the opening 84, freeing the shafts for independent rotation for the purposes now to be described- From the foregoing the method of constructing and using my improved apparatus together with the advantages thereof may now be more fully explained and understood.

With the apparatus in place onthe carburetor of an engine as illustrated and connected to the intake manifold vacuum as shown, when the engine is idle the throttle valves 12 are opened when the accelerator pedal is depressed. This'is due to the connectionof the piston; 83 which locks the shafts 32 and 33 together. As soon as the engine starts vacuum is applied through opening 88 to the right-handmost end of the cylinder 82 as viewed in Fig. 6, thus withdrawing the detent end 84 of the piston 83 from the opening 86. With the engine idling the parts are as shown in Figs. 3 and 4 with the exception, of course, that the shafts 32 and 3-3 are free to rotate clockwise as viewed in Fig. 3, independently of each other. When the accelerator is opened the stop 77 is moved clockwise as viewed in Fig. 3. With the engine under no load it will be apparent that the vane assembly between the plates 57 and 58 will move to the right as viewed in Fig. 3, opening the throttle valves 12 to such a position that the vacuum exerted in the compartment or section 43 equals the pull of the spring 78 or the weight 81, as the case may be. The amount of this opening will be determined by the strength of the spring 78 or the weight 81 as limited by the amount of clockwise movement of stop 77, the latter, as stated, being determined by the manual throttle control means. It will further be seen that the engine will open its own throttle in accordance with the optimum amount of fuel that it can use inasmuch as this optimum amount of fuel is in direct proportion to the vacuum in the intake manifold, under all conditions. Therefore, when the stop moves to the right the throttle valves are freed for opening to the optimum position in accordance with the manifold 'vacuum.

At the usual automobile cruising speeds of say 60 to 70 miles an hour it will be understood that the pressure in the manifold of the engine is lower than it is when the engine is idling or when it is running at lower speeds, at part throttle. Therefore, in view of the increasing effective area of the vanes carried between the plates 5758 and 59-61 as they rotate clockwise, the throttle will be held in more fully open position with lower pressure in the manifold at nearly full throttle open position than at closed or part open throttle position. I thus assure that the throttle in fact is held in the optimum position at high speeds so that the engine at such high speeds is fully charged with fuel upon each stroke of the pistons.

My invention is further characterized by the fact that! with it applied to an internal combustion engine I can increase the compression ratio considerably above the ratios currently employed in automobile engines. For instance, I have increased the compression ratio of a standard eight-cylinder 1958 model Chevrolet automobile engine from 9.2 to approximately 11. With my invention applied to such engine I have been able to operate the same on fuels of an octane rating of around 80 and have improved the etficiency thereof without losing any of the desired performance. This is brought about due to the fact that it is impossible with my invention applied to such an engine to damage the engine by suddenly kicking down the throttle at very low speeds. In that connection it will be apparent that the metered opening 51 holds the throttle vane shaft assembly against sudden clockwise rotation, in the event the throttle pedal is suddenly kicked down. This prevents overloading the engine with fuel at low engine r.p.m., resulting in protecting the engine and saving fuel.

From the foregoing it will be seen that my invention is particularly characterized by the fact that it assures that at high speeds the engine is adequately charged while at low speeds the engine is not overcharged. This permits the compression ratio of such engine to be raised materially without damage to the engine.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited; but is susceptible of various changes modifications without departing from the spirit thereof,

, appended claims.

What. I claim is:

1. In throttle control means for internal combustion engines having an intake manifold and a manually operated throttle valve control, a substantially fluid-tight chamber having at least some portions of its inner peripheral walls curved, end walls for the chamber, a pair of concentrically disposed independently movable shafts disposed in the chamber adjacent the center thereof, vanes on the shafts dividing the chamber into two sections and having portions making substantially fluid-tight sealing contact with the curved peripheral walls and said end walls, means connecting one section of said chamber to the atmosphere, means connecting the other section to the sub-atmospheric pressure in the intake manifold, means connecting one of said shafts to the manual throttle control and the other thereof to the throttle valve of the carburetor, and stop means for mechanically limiting rotation of the shaft connected to the throttle valve in response to rotation of the other shaft upon actuation of the manual throttle control.

2. The combination with an internal combustion engine having an intake manifold and a carburetor with a throttle valve therein, and a manually operable throttle member, of a substantially fluid-tight chamber having a pair of movable vanes therein dividing the chamber into two sections one of which is maintained substantially fluid-tight by the vanes and the other of which is connected to the atmosphere, 2. connection from the fluidtight chamber to the manifold whereby a chamber bounded by common sides of the vanes is subjected to the sub-atmospheric pressure existing in the manifold, means mounting the vanes for movement in a common direction of rotation, means operatively connecting one of said vanes for movement toward the atmospheric pressure side thereof in response to throttle opening movement of the control member, and stop means operable upon movement of the throttle member controlled vanes effective to free the other of said vanes for movement toward throttle valve open position in response to the subatmospheric pressure existing in the manifold.

3. The combination with an internal combustion engine having an intake manifold and a carburetor with a throttle valve therein together with a manually operable throttle member, of a chamber having therein a pair of independently movable vanes which maintain a part of the chamber substantially fluid-tight in all positions of said vanes, a pressure transmitting connection between said part of the chamber and the intake manifold, means manually to move one of said vanes in a direction to increase the volume of the fluid-tight part of the chamber, means connecting the other of said vanes to the engine throttle valve whereby rotation thereof moves the throttle valve, and a stop associated with the manually movable vane effective to limit the throttle valve opening in accordance with the setting of the manually movable vane.

4. Apparatus as defined in claim 3 in which the effective cross sectional area of the vanes increases as the parts are moved toward open throttle position.

5. Apparatus as defined in claim 3 in which the chamber containing said vanes has curved walls against which the ends of the vanes slide, said walls being curved on an increasing radius relative to the ends of the vanes, whereby upon movement of the parts toward open throttle position the effective area of the vanes increases, and means urging the vanes into sealing contact with said curved walls.

6. Apparatus as defined in claim 3 in which the movement toward open throttle position of the vane connected to the throttle valve is pneumatically retarded, whereby sudden movement towards open throttle position of themanually controlled vane does not correspondingly and suddenly move the throttle valve vane toward open throttle position.

8 References Cited in the file of this patent UNITED :sTATEs PATENTS 

